Multiband RoF System with Good Transmission Performance Based on Additional SCS

A wavelength division multiplexing radio-over-fiber (WDM-RoF) system that can support multiband radio signals based on an additional subcentral station (SCS) is proposed and demonstrated in this paper. The dispersion characteristics of the multiband radio signals over fiber transmission are explored, and we exploit an improved transmission structure consisting of the central station (CS), the SCS, and base stations (BSs) to optimize the antidispersion performance of the proposed RoF system. At the SCS, a dual-drive Mach-Zehnder modulator (MZM) is employed to realize a cost-effective multiband radio signal generation of WDM signals with great spectral flatness, and an optical cross-connect unit is utilized to achieve a flexible distribution of different band radio signals for remote BSs. Based on the additional SCS, we establish a verification WDM-RoF system, which can support reliable transmission of multiband radio signals including 13 GHz, 26 GHz, 39 GHz, and 52 GHz. The WDM signals with each data rate at 2.5 Gbps are successfully transmitted over a 40 km standard single-mode fiber.